Conductor Sentence Examples

As it came to a stop the conductor called out in a loud voice.

Glass is a bad conductor of heat.

This elevated conductor is now called the antenna, aerial wire, or air wire.

The crucible was surrounded with a bad conductor of heat to minimize loss by radiation.

The conductor said it was the worst quake he ever knew.

Assuming the materials to be of equal tensile strength per unit of area - hard-drawn copper is stronger, but has a lower conductivity - the adoption of aluminium thus leads to a reduction of 52% in the weight, a gain of 60% in the strength, and an increase of 26% in the diameter of the conductor.

The insulated conductor to which the points are connected therefore becomes positively electrified.

Next let the balls A' and B' be connected together for a moment by a wire N called a neutralizing conductor which is subsequently removed.

The wire which connects two armature plates for a moment is the neutralizing conductor.

The length of the beds is regulated by the supply of water and the fall from the conductor to the main drain.

The choir performs major choral works twice a year under conductor Stephen Rhys, MBE.

Jiri Belohlavek became Assistant Conductor with the Czech Philharmonic upon graduation from the Prague Academy of Arts where he studied with Celibidache.

For a smaller group, I think a conductor looks pretentious!

Its role then, and subsequently, was to act as a lightning conductor channeling working class radicalism safely to earth.

Early in 1935 both tracks were again re-laid, this time with the addition of an electric conductor rail.

Josef Strauss died young - in 1870, aged 42, after collapsing on the conductor's rostrum.

Talented conductor Dominc Wheeler will be joined by soloists from Opera Interludes.

The guest soloist and conductor for the evening was internationally acclaimed tuba soloist Steve Sykes.

It is also unusual for the very fast tempi taken by the conductor.

Electricity Overhead lines carry 25,000 volts AC, conductor rails carry 750 volts DC.

Suppose next that a fixed insulated conductor is somehow kept at the potential of the air at a given point, then the measurement of its potential is equivalent to a measurement of that of the air.

The matter leaving the conductor, whether the products of combustion or the drops of a liquid, supplies the means of securing equality of potential between the conductor and the air at the spot where the matter quits electrical connexion with the conductor.

It was of course well known, as a necessity of Maxwell's mathematical theory, that the polarization and depolarization of an insulator must give rise to the same electromagnetic effects in the neighbourhood as a voltaic current in a conductor.

In 1840 he showed that when an electric current was produced by means of a dynamo-magneto-electric machine the heat generated in the conductor, when no external work was done by the current, was the same as if the energy employed in producing the current had been converted into heat by friction, thus showing that electric currents conform to the principle of the conservation of energy, since energy can neither be created nor destroyed by them.

Le Sage proposed a similar method, in which each conductor was to be attached to a pith ball electroscope.

The actual speed or rate of signalling is given approximately by the formula, S = 120/ (KR), where S is the number of words per minute, R the total resistance of the conductor in ohms, and K the total capacity in farads.

The conductor, which was a wooden casing of somewhat greater internal diameter than the maximum bore of the well, passed through the first of these divisions, and casing was used in the second to prevent percolation of water into the oil-bearing portion.

An electric current in a conductor is recognized by its ability (a) to create heat in a wire through which it passes, (b) to produce a magnetic field round the conductor or wire.

The heat makes itself evident by raising the temperature and therefore elongating the wire, whilst the magnetic field creates mechanical forces which act on pieces of iron or other conductors conveying electric currents when placed in proximity to the conductor in question.

A symphony was produced at the Gewandhaus concerts in 1833, and in the following year he was appointed conductor of the opera at Magdeburg.

Being a bad conductor of electricity it is of value as an insulator, and the smooth flexible sheets are much used in the construction of armatures of dynamos and in other electrical machinery.

Lincei, 1883-1884, 19, 545) showed that a more considerable alteration was produced when the magnetic force was applied transversely to the bismuth conductor; he also noticed that the effect was largely dependent upon temperature (see also P. Lenard, Wied.

From these and other considerations it is obvious that (I) the electrolyte must be such as will freely dissolve the metal to be refined; (2) the electrolyte must be able to dissolve the major portion of the anode, otherwise the mass of insoluble matter on the outer layer will prevent access of electrolyte to the core, which will thus escape refining; (3) the electrolyte should, if possible, be incapable of dissolving metals more electro-negative than that to be refined; (4) the proportion of soluble electro-positive impurities must not be excessive, or these substances will accumulate too rapidly in the solution and necessitate its frequent purification; (5) the current density must be so adjusted to the strength of the solution and to other conditions that no relatively electro-positive metal is deposited, and that the cathode deposit is physically suitable for subsequent treatment; (6) the current density should be as high as is consistent with the production of a pure and sound deposit, without undue expense of voltage, so that the operation may be rapid and the "turnover" large; (7) the electrolyte should be as good a conductor of electricity as possible, and should not, ordinarily, be altered chemically by exposure to air; and (8) the use of porous partitions should be avoided, as they increase the resistance and usually require frequent renewal.

It follows from this that the electric force at the surface of the conductor has no component along the surface, in other words, the electric force at the bounding surface of the conductor and insulator is everywhere at right angles to it.

The Poisson equation cannot, however, be applied in the above form to a region which is partly within and partly without an electrified conductor, because then the electric force undergoes a sudden change in value from zero to a finite value, in passing outwards through the bounding surface of the conductor.

Again the shunt circuit must have practically zero inductance and the series or current coil must be wound or constructed with stranded copper wire, each strand being silk Covered, to prevent the production of eddy currents in the mass of the conductor.

It is a good conductor of heat, and therefore feels colder to the touch than glass and imitation stones.

Gauntlett became organist at Union Chapel and conductor of a psalmody class.

Metallic selenium is a conductor of electricity, and its conductivity is increased by light; this property has been utilized in apparatus for transmitting photographs by telegraphy (see Telegraph).

In 1884 his Rose of Sharon was given with very great success at the Norwich Festival; in 1885 he was appointed conductor of Novello's oratorio concerts; The Story of Sayid came out at the Leeds Festival of 1886; and in 1888 he succeeded Macfarren as principal of the Royal Academy of Music. The Dream of Jubal was produced at Liverpool in 1889, and in London very soon afterwards.

Josef Strauss died young - in 1870, aged 42, after collapsing on the conductor 's rostrum.

Each conductor was provided with a sentry box in which to sit whilst he was waiting for a fire call.

Silver-plated conductor wires, enhanced by deep Cryogenic Treatment and insulated in PTFE.

You do n't see an orchestra play without a conductor, and you do n't see a string quartet play with a conductor.

Semi conductor thermoelectric device which works on the Peltier effect.

However, although a changed man, he was pronounced fit in 1923 and became a tram conductor for Hull Corporation.

It is important for any conductor to be able to understand fully what is meant by a transposition row.

They are made of a light type of silicon coating that is applied in thin layers and that acts as a conductor.

Basically a generator consists of a set of magnets and a conductor like a coiled wire.

Stainless steel is the poorest conductor of heat among metal pans, but it is most widely used because it does not cause any chemical reactions to food and is virtually maintenance free.

Classical Orchestra Musician- These musicians play amazing music and are for the most part directed by their conductor.

Jacques Singer, Marc's father, was a symphony conductor, while his mother Leslie was a pianist.

Aluminum is a thermal conductor, so in cold weather heat will drain out through the sash, as moisture will condense on interior surfaces.

It's not just the conductor and the musicians who can wear their tuxedos - opera goers are usually encouraged to dress their best.

When the space heater is turned on, the infrared Quartz light bulbs produce the infrared rays that get absorbed by the heat exchanger, which is usually made out of a good heat conductor like copper.

Finish the look with a Thomas-themed rug or wall-paper border and add one junior conductor to complete the room.

Copper is an excellent conductor and transmits data in frequencies.

In non-musical work, Starr spent a season playing Mr. Conductor on the PBS children's program Shining Time Station.

The score for Slumdog Millionaire was created by famed conductor A.R.

The conductor at the time was Serge Koussevitzky.

The most famous of these events was when composer and conductor Leonard Bernstein made his final live concert appearance there in August 1990.

Stephen Oremus arranged the music and also worked as musical supervisor and conductor alongside James Lynn Abbott.

In 1938 the hard hat material was switched to aluminum, which was lightweight and durable, but a conductor of electricity.

The hat was not a good conductor of electricity, making it a safer choice than its previous counterparts; it was made from polyethylene plastic that was treated with an ultraviolet inhibitor.

Let a conductor, say a metallic sphere, be supported by a metal rod of negligible electric capacity whose other end is earthed.

Linss (6) found that an insulated conductor charged either positively or negatively lost its charge in the free atmosphere; the potential V after time t being connected with its initial value Vo by a formula of the type V = Voe - at where a is constant.

The lime deposit or " fur " is a poor conductor of heat, and it is therefore most detrimental to the efficiency of the system to allow the interior of the boiler or any other portion to become furred up. Further, if not removed, the fur will in a short time bring about a fracture in the boiler.

It appears, however, to depend upon the fact that an electric arc is not like a solid conductor.

In those intended for alternating currents, the main current through the movable coil, whether consisting of one turn or more than one turn, is carried by a wire rope, of which each component strand is insulated by silk covering, to prevent the inductive action from altering the distribution of the current across the transverse section of the conductor.

If the conductor consists of a coil of wire the ends of which are connected with a suitable galvanometer, the integral electromotive force due to a sudden increase or decrease of the induction through the coil displaces in the circuit a quantity of electricity Q=SBns R, where SB is the increment or decrement of induction per square centimetre, s is the area of the coil, n the number of turns of wire, and R the resistance of the circuit.

Hall, the positive sign indicating that the electromotive force is in the same direction as the mechanical force acting upon the conductor.

A charged conductor supported on a non-conductor retains its charge.

This shows that the two electricities neutralize each other's effect when imparted equally to the same conductor.

If we consider a very small conductor charged with a unit of positive electricity to be placed in an electric field, it will move or tend to move under the action of the electric force in a certain direction.

From this fact it follows that we can shield any conductor entirely from external influence by other "charged conductors by enclosing it in a metal case.

Even if a charged and insulated conductor, such as an open canister or deep cup, is not perfectly closed, it will be found that a proof-plane consisting of a small disk of gilt paper carried at the end of a rod of gum-lac will not bring away any charge if applied to the deep inside portions.

In fact it is curious to note how large an opening may be made in a vessel which yet remains for all electrical purposes " a closed conductor."

Another corollary of the fact that there is no electric force in the interior of a charged conductor is that the potential in the interior is constant and equal to that at the surface.

If we consider the charge of a conductor to be measured by the number of tubes of electric force which proceed from it, then, since each tube must end on some other conductor, the above statement is equivalent to saying that the charges at each end of a tube of electric force are equal.

We must next consider the quality of a conductor called its electrical capacity.

The potential of a conductor has already been defined as the mechanical work which must be done to bring up a very small body charged with a unit of positive electricity from the earth's surface or other boundary taken as the place of zero potential to the surface of this conductor in question.

The capacity of a conductor is defined to be the charge required to raise its potential to unity, all other charged conductors being at an infinite distance.

This capacity is then a function of the geometrical dimensions of the conductor, and can be mathematically determined in certain cases.

Since the potential of a small charge of electricity dQ at a distance r is equal to dQ/r, and since the potential of all parts of a conductor is the same in those cases in which the distribution of surface density of electrification is uniform or symmetrical with respect to some point or axis in the conductor, we can calculate the potential by simply summing up terms like rdS/r, where dS is an element of surface, o- the surface density of electricity on it, and r the distance from the symmetrical centre.

This formula is important in connexion with the capacity of electric cables, which consist of a cylindrical conductor (a wire) enclosed in a conducting sheath.

Cavendish and subsequently Faraday discovered this fact, and the latter gave the name " specific inductive capacity," or " dielectric constant," to that quality of an insulator which determines the charge taken by a conductor embedded in it when charged to a given potential.

It is worth noting that if we have a charged sphere we can perfectly discharge it by introducing it into the interior of another hollow insulated conductor and making contact.

In the next place apply the surface characteristic equation to any point on a charged conductor at which the surface density is a.

The above is a statement of Coulomb's law, that the electric fores at the surface of a conductor is proportional to the surface density of the charge at that point and equal to 41r times the density.3 See Maxwell, Electricity and Magnetism, vol.

Accordingly, since every tube sent out from a charged conductor must end somewhere on another charge of opposite sign, it follows that the two electricities always exist in equal quantity, and that it is impossible to create any quantity of one kind without creating an equal quantity of the opposite sign.

Since the potential of a conductor is defined to be the work required to move a unit of positive electricity from the surface of the earth or from an infinite distance from all electricity to the surface of the conductor, it follows that the work done in putting a small charge dq into a conductor at a potential v is v dq.

Let us then suppose that a conductor originally at zero potential has its potential raised by administering to it small successive doses of electricity dq.

If a is the surface density and dS an element of surface, then fadS is the whole charge, and hence afV adS is the expression for the energy of charge of a conductor.

Thus the actual distribution of electricity on the conductor in the field is not merely a stable distribution, it is the only possible stable distribution.

In both forms it is usual to have the space between the bulb and the protecting sheath partly filled with mercury or alcohol to act as a conductor and reduce the time necessary for the thermometer to acquire the temperature of its surroundings.

Ice is a very poor conductor of heat and accordingly protects the surface of the water beneath from rapid cooling; hence new-formed pancake ice does not increase excessively in thickness in one winter, and even in the centre of the Arctic Basin the ice-covering only amounts to 6 or at most 9 ft.

For the purpose of measuring resistances up to a few thousand ohms, the most convenient appliance is a Wheatstone's Bridge (q.v), but when the resistance of the conductor to be measured is several hundred thousand ohms, or if it is the resistance of a so-called insulator, such as the insulating covering of the copper wires employed for distributing electric current in houses and buildings for electric lighting, then the ohmmeter is more convenient.

Music is much cultivated, and there is an opera with a first-rate orchestra, of which Ludwig Spohr was at one time conductor.

The mass of mercury is thus set in motion owing to the tendency of a conductor conveying an electric current to move transversely across lines of magnetic force; it becomes in fact the armature of a simple form of dynamo, and rotates with a speed which increases with the strength of the current.

Matthiessen, sodium ranks fourth to silver, copper and gold as a conductor of electricity and heat, and according to Bunsen it is the most electropositive metal with the exception of caesium, rubidium and potassium.

Graphite is black and opaque, whilst diamond is colourless and transparent; it is one of the softest (H= I) of minerals, and diamond the hardest of all; it is a good conductor of electricity, whilst diamond is a bad conductor.

It is a very dense form of carbon, and is a good conductor of heat and electricity.

With the increasing price of copper, it is coming into vogue as an electrical conductor for uncovered mains; it is found that an aluminium wire 0.126 in.

Nairne's machine could give either positive or negative electricity, the first named being collected from the prime conductor carrying the collecting points and the second from the prime conductor carrying the cushion.

In the course of their rotation two diametrically opposite carriers touched against the ends of a neutralizing conductor so as to form for a moment one conductor, and the moment afterwards these two carriers were insulated, one carrying away a positive charge and the other a negative.

Each upright bearing carrying the shafts of the revolving disks also carries a neutralizing conductor or wire ending in a little brush of gilt thread.

The second point of primary importance is the size and slope of the main conductor, which brings the water from the river to the meadow.

The stuff taken out of the conductor should be employed in making up its banks or correcting inequalities in the meadow.

That portion of the ground which is to be watered by one conductor should be made into beds to suit the circumstances of that conductor; that is, instead of the beds over the meadow being all reduced to one common level, they should be formed to suit the different swells in the ground, and, should any of these swells be considerable, it will be necessary to give each side of them its respective conductor.

The beds should run at or nearly at right angles to the line of the conductor.

The beds thus formed should slope in an inclined plane from the conductor to the main drain, that the water may flow equably over them.

The depth of the feeders is the same in relation to the conductor.

For the more equal distribution of the water over the surface of the beds from the conductor and feeders, small masses, such as stones or solid portions of earth or turf fastened with pins, are placed in them, in order to retard the momentum which the water may have acquired.

Heaps of stones answer very well for stops in the conductor, particularly immediately below the points of junction with the feeders.

The distribution of the water over the whole meadow is regulated by the sluices, which should be placed at the origin of every conductor.

A small sluice placed in the side of the conductor opposite to the meadow, and at the upper end of it, will drain away the leakage that may have escaped from the head sluice.

Let the stript ground then be neatly formed with the spade and barrow, into beds varying in breadth and shape according to the nature of the soil and the dip of the ground - the feeders from the conductor and the small drains to the main drain being formed at the same time.

In such a case the main drain of a watered meadow may form the conductor of the one to be watered, or a new conductor may be formed by a prolongation of the main drain; but either expedient is only advisable where water is scarce.

Where it is plentiful, it is better to supply the second meadow directly from the river, or by a continuation of the first main conductor.

Stirring Is Effected By Causing The Water To Circulate Spirally Round The Bulbs Of The Thermometers And The Heating Conductor As Indicated In The Figure.

In The Case Of Water Or Other Liquids It Is Necessary To Employ A Platinum Wire Stretched Along The Tube As Heating Conductor.

The bottle was held in the hand, and the nail presented to the prime conductor of an electrical machine.

In using the instrument the insulated rod to which the gold-leaf is attached is connected to the conductor, the potential of which is being examined.

His appeal to musicians was made in a threefold capacity, and we have, therefore, to deal with Liszt the unrivalled pianoforte virtuoso (1830 - r848); Liszt the conductor of the "music of the future " at Weimar, the teacher of Tausig, Billow and a host of lesser pianists, the eloquent writer on music and musicians, the champion of Berlioz and Wagner (1848-1861); and Liszt the prolific composer, who for some five-and-thirty years continued to put forth pianoforte pieces, songs, symphonic orchestral pieces, cantatas, masses, psalms and oratorios (1847-1882).

As virtuoso he held his own for the entire period during which he chose to appear in public; but the militant conductor and prophet of Wagner had a hard time of it, and the composer's place is still in dispute.

During this period he acted as conductor at court concerts and on special occasions at the theatre, gave lessons to a number of pianists, wrote articles of permanent value on certain works of Berlioz and the early operas of Wagner, and produced those orchestral and choral pieces upon which his reputation as a composer mainly depends.

They came originally from Britain, and Ursula was the conductor and encourager of the holy troop."

If, however, pairs of metallic disks, made, say, of zinc and copper, are alternated with disks of cloth wetted with a conductor of the second class, such, for instance, as dilute acid or any electrolyte, then the effect of the feeble potential difference between one pair of copper and zinc disks is added to that of the potential difference between the next pair, and thus by a sufficiently long series of pairs any required difference of potential can be accumulated.

It is clear, moreover, that Oersted clearly recognized the existence of what is now called the magnetic field round the conductor.

Ampere had already previously shown that a spiral conductor or solenoid when traversed by an electric current possesses magnetic polarity, and that two such solenoids act upon one another when traversed by electric currents as if they were magnets.

It led at once to the construction of the galvanometer as a means of detecting and measuring the electric current in a conductor.

Ampere's investigations had led electricians to see that the force acting upon a magnetic pole due to a current in a neighbouring conductor was such as to tend to cause the pole to travel round the conductor.

Faraday and others then discovered, as already mentioned, means to make the conductor conveying the current rotate round a magnetic pole, and Ampere showed that a magnet could be made to rotate on its own axis when a current was passed through it.

Fully familiar with the fact that an electric charge upon one conductor could produce a charge of opposite sign upon a neighbouring conductor, Faraday asked himself whether an electric current passing through a conductor could not in any like manner induce an electric current in some neighbouring conductor.

He then found that a conductor, the ends of which were connected respectively with the centre and edge of the disk, was traversed by an electric current.

He proved by systematic experiments that the electromotive forces set up in conductors by their motions in magnetic fields or by the induction of other currents in the field were due to the secondary conductor cutting lines of magnetic force.

He invented the term " electrotonic state " to signify the total magnetic flux due to a conductor conveying a current, which was linked with any secondary circuit in the field or even with itself.

The fundamental fact connecting electric currents and magnetic fields is that the line integral of magnetic force taken once round a conductor conveying an electric current is equal to 4 7r-times the surface integral of the current density, or to 4 7r-times the total current flowing through the closed line round which the integral is taken (see Electrokinetics).

To take a simple instance, if we consider an electric current as flowing in a conductor it is, as Oersted discovered, surrounded by closed lines of magnetic force.

If we imagine the current in the conductor to be instantaneously reversed in direction, the magnetic force surrounding it would not be instantly reversed everywhere in direction, but the reversal would be propagated outwards through space with a certain velocity which Maxwell showed was inversely as the square root of the product of the magnetic permeability and the dielectric constant or specific inductive capacity of the medium.

Weber had already laid the foundations of the absolute system of electric and magnetic measurement, and proved that a quantity of electricity could be measured either by the force it exercises upon another static or stationary quantity of electricity, or magnetically by the force this quantity of electricity exercises upon a magnetic pole when flowing through a neighbouring conductor.

Canton (1 753, 1 754) When, for instance, a positively electrified body was found to induce upon another insulated conductor a charge of negative electricity on the side nearest to it, and a charge of positive electricity on the side farthest from it, this was explained by saying that the particles of each of the two electric fluids repelled one another but attracted those of the positive fluid.

Hence the operation of the positive charge upon the neutral fluid was to draw towards the positive the negative constituent, of the neutral charge and repel to the distant parts of the conductor the positive constituent.

After passing the last pair of workers and strippers the fibre is carried forward towards the doffing roller, the pins of which are back-set, and the fibre is removed from the cylinder by the doffer, from which it passes between the drawing and pressing rollers into the conductor, and finally between the delivery and pressing rollers into the sliver can.

If then two experiments are made, first with the upper plate connected to earth, and secondly, connected to the object being tested, we get an expression for the potential V of this conductor in the form V=A(d' - d), where d and d' are the distances of the fixed and movable plates from one another in the two cases, and A is some constant.

First one and then the other conductor is connected with the electrode of the lower or movable plate, which is moved by the screw until the index attached to the attracted disk shows it to be in the sighted position.

Haydn was for thirty years conductor of his private orchestra and general musical director, and many of his compositions were written for the private theatre and the concerts of this prince.

In 1834 he continued and extended his researches "On the Influence of a Spiral Conductor in increasing the Intensity of Electricity from a Galvanic Arrangement of a Single Pair," a memoir of which was read before the American Philosophical Society on the 5th of February 1835.

He was appointed precentor of St George's Church in 1870, and conductor of the Scottish vocal music association in 1873, at the same time getting through a prodigious amount of teaching.

Trumpator was a son of Conductor, who was by Matchem out of a mare by Snap.

His best son was Conductor (1767) out of a mare by Snap; Conductor was the sire of Trumpator (1782), whose two sons, Sorcerer (1790) and Paynator (1791), transmit the blood of the Godolphin down to modern times.

Thus there is left a space between the two hoods through which the sound of the orchestra ascends with wonderfully blended effect; the conductor, sitting at the highest point of the orchestra, though under the screen, has a complete view of the stage as well as of his instrumentalists, and the sound of the orchestra is sent most forcibly in the direction of the stage, so that the voices are always well supported.

When we first came out, I remember these notes pinned to us telling the conductor and everyone who cared who we were and where we were going so we didn't get lost.

He studied bassoon and choral and orchestral conducting, and began his career as teacher and conductor.

Or to conduct an orchestra in the Wii launch game called Music, simply wave it around like a conductor's baton.

In 1935 he was appointed full time conductor of the band.

Transmission line with exposed conductor surfaces can experience oxidation and an increase in losses due to skin effect heating.

A Graduate of the Royal Northern College of Music, Susan divides her time between being a music educator and a choral conductor.

The invitation follows his recent success working with the renowned conductor at the Offenbach Festival at the Lyon Opera House in France.

There are now around 47 semi conductor manufacturing plants in the UK alone.

In the same year he was appointed principal conductor of the Varese Ensemble.

Just inside the bore of the permanent magnet is a resistive magnet, made from copper conductor in a saddle configuration.

The hybrid coupler shown to the left is made of square coaxial cable with inner conductor only a 50 micron wide.

It's seven o'clock sharp and the conductor gives the downbeat for the brass band to begin.

The conductor said, " Rogers, I believe you're a damn fool.

We have used the transparent conductor indium tin oxide to fabricated electrode arrays with approximately 500 electrodes spaced at 60 Am.

In 1969 he was appointed conductor laureate of the orchestra for life.

Oscar nominated Ron Moody, Special Guest Conductor Laurie Johnson.

He was the first conductor at St Paul's Cathedral, calling the 1st peal there on 10th Dec. 1881.

The body is an excellent conductor, and electric current from any source passing through the body produces electric shock injuries.

Wet clothing readily draws heat away from the skin because water is a potent conductor of heat.

With battery-operated lights and sounds and working parts, he will feel like the conductor of his very own train station.

Flannel is a natural electricity conductor.

Similarly, for kids who like trains, you can even dress up like a conductor and set up a model train set while telling children facts about trains, reading a book about trains and then singing a song.

Faraday's term " electrode," literally " a way (650s) for electricity to travel along," might be well applied to designate the insulated conductor along which the electric messenger is despatched.

We may define the term potential difference otherwise by saying that it is the work done in carrying a small conductor charged with one unit of electricity from one point to the other in a direction opposite to that in which it would move under the electric forces if left to itself.

Suppose then that we have a conductor charged with electricity,we may imagine its surface to be divided up into small unequal areas, each of which carries a unit charge of electricity.

If we consider lines of electric force to be drawn from the boundaries of these areas, they will cut up the space round the conductor into tubular surfaces called tubes of electric force, and each tube will spring from an area of the conductor carrying a unit electric charge.

Hence the charge on the conductor can be measured by the number of unit electric tubes springing from it.

The surface of a charged conductor is an equipotential surface, because when the electric charge is in equilibrium there is no tendency for electricity to move from one part to the other.

We call the difference of potential between a charged conductor and the earth the potential of the conductor.

An electrified conductor is a store of energy, and from the definition of potential it is clear that the work done in increasing the charge q of a conductor whose potential is v by a small amount dq, is vdq, and since this added charge increases in turn the potential, it is easy to prove that the work done in charging a conductor with Q units to a potential V units is z QV units of work.

This harmonizes with the fact that the real seat of the energy 3f electrification is the dielectric or insulator surrounding the charged conductor.'

By the surface density of electrification on a conductor is meant the charge per unit of area, or the number of tubes of electric force which spring from unit area of its surface.

Coulomb proved experimentally that the electric force just outside a conductor at any point is proportional to the electric density at that point.

It can be shown that the resultant electric force normal to the surface at a point just outside a conductor is 1 See Maxwell, Elementary Treatise on Electricity (Oxford, 1881), P. 47.

The thinnest possible spherical shell of metal, such as a sphere of insulator coated with gold-leaf, behaves as a conductor for static charge just as if it were a sphere of solid metal.

On his return to Vienna in 1756 he became famous as teacher and composer, in 1759 he was appointed conductor to the private band of Count Morzin, for whom he wrote several orchestral works (including a symphony in D major erroneously called his first), and in 1760 he was promoted to the sub-directorship of Prince Paul Esterhazy's Kapelle, at that time the best in Austria.

In the Odyssey, however, he appears mainly as the messenger of the gods, and the conductor of the dead to Hades.

The conductor of souls was naturally a chthonian god; at Athens there was a festival.

In 1840 he ', as thus enabled to give a quantitative statement of the law acc s rding to which heat is produced in a conductor by the pas ageof an electric current, and in succeeding years he publish d a series of valuable researches on the agency of electricity in ansformations of energy.

The lower ends of these wires are connected through the secondary coil of an oscillation transformer to an earth plate, or to a large conductor placed on or near the earth called a " balancing capacity."

The density of solid sulphur is 2 062 to 2'070, and the specific heat 0.1712; it is a bad conductor of electricity and becomes negatively electrified on friction.

He ascertained the distribution of electricity among several spheres (whether equal or unequal) placed in contact in a straight line; and he measured the distribution of 2 In 1878 Clerk Maxwell repeated Cavendish's experiments with improved apparatus and the employment of a Kelvin quadrant electrometer as a means of detecting the absence of charge on the inner conductor after it had been connected to the outer case, and was thus able to show that if the law of electric attraction varies inversely as the nth power of the distance, then the exponent n must have a value of 2 t Isua.

Distilled water is a very bad conductor, though, even when great care is taken to remove all dissolved bodies, there is evidence to show that some part of the trace of conductivity remaining is due to the water itself.

A magnetic field is generally due either to a conductor carrying an electric current or to the poles of a magnet.

The field at the centre of a circular conductor of radius r through which current is passing is H = 27ri/r, (3) the direction of the force being along the axis and related to the direction of the current as the thrust of a corkscrew to its rotation.

This provides us with a definition of a unit of electric force, for it is the strength of an electric field at that point where a small conductor carrying a unit charge is acted upon by unit mechanical force, assuming the dielectric constant of the surrounding medium to be unity.

He had accepted an engagement there as conductor; but, the lessee becoming bankrupt, the scheme was abandoned in favour of a better appointment at Riga.

Caoutchouc is a bad conductor of heat and electricity, and alone or mixed with other materials is employed as an electrical insulator.

Connexion is made into the office (or to the underground system, as is often the case) from the aerial wire by means of a copper conductor, insulated with gutta-percha, which passes through a " leading in " cup, whereby leakage is prevented between the wire and the pole.

The central conductor is covered with several continuous coatings of guttapercha, the total weight of which varies between 70 and 650 lb to the mile.

Being a bad conductor of heat it is used for the packing and jackets of boilers and steam-pipes.

Theoretically for a given outside diameter of core the greatest speed of signalling through a cable is obtained when the diameter of the conductor is 606 (1/,/e) the diameter of the core, but this ratio makes the thickness of the guttapercha covering insufficient for mechanical strength.

A large number of such sheets are prepared and placed together, one over the other, the end of the strip of the first sheet being connected with the beginning of the strip of the second, and so on to the last sheet, the whole representing the conductor of the cable.

The conductor of the cable is practically insulated, as the condensers in the bridge have a very high resistance; hence no appreciable current ever flows into or out of the line.

Increase in the voltage acting upon a solid conductor increases the current through it, but in the case of the electric arc an increase in current is accompanied by a fall in the difference of potential of the carbons, within certain limits, and the arc has therefore been said to possess a negative resistance.'

The action was started in the cold, the alkali being slightly moistened to render it a conductor; then, as the current passed, heat was produced and the alkali fused, the metal being deposited in the liquid condition.

The conductor helped her off the car and then the engineer started his train again, so that it puffed and groaned and moved slowly away up the track.

In the earliest the conductor was represented by long metal wires, supported by silk or other insulating material, and left to pick up the air's potential.

The leakage through the insulator of the cable is compensated for by connecting high resistances between different points of the strip conductor and the earth coating.

In later wells the conductor has been replaced with an 8-in.

This solution, being an inferior conductor of electricity, requires a much higher electromotive force to drive the current through it, and is therefore more costly in use.

The modern Wagnerian conductor is apt to complain that Beethoven, in his four-bar phrase, drowns a melody which lies in the weakest register of the clarinet by a crowd of superfluous notes in oboes, horns and flutes.

The first requisite for electro-telegraphic communication between two localities is an insulated conductor extending from one to the other.

Gutta-percha-covered copper wires were formerly largely used for the purpose of underground lines, the copper conductor weighing 40 lb per statute mile, and the gutta-percha covering 50 lb (90 lb total).

One end of the sensitive tube was then connected to the earth and the other end to an antenna or insulated elevated conductor A2.

This mode of suspension enables the conductor CC to vibrate freely like a balance, but at the same time very large currents can easily be passed through this perfectly flexible joint.

Sir Michael Costa was the conductor 1846-1854, and from his acceptance of that high pitch the fork became known as Costa's, and its inception was attributed to him, though on insufficient grounds.

Depending on the fact that the electrical conductivity of a metallic conductor is decreased by heat, it consists of two strips of platinum, arranged to form the two arms of a Wheatstone bridge; one strip being exposed to a source of radiation from which the other is shielded, the heat causes a change in the resistance of one arm, the balance of the bridge is destroyed, and a deflection is marked on the galvanometer.

The conductor, too, was kind.

Pupin showed that by placing inductance coils in circuit, at distances apart of less than half the length of the shortest component wave to be transmitted, a non-uniform conductor could be made approximately equal to a uniform conductor.

The end is taken into the testing room in the cable-house and the conductor connected with the testing instruments, and, should the electrical tests continue satisfactory, the ship is put on the proper course and steams slowly ahead, paying out the cable over her stern.

This experiment proves that when a charged body acts by induction on an insulated conductor it causes an electrical separation to take place; electricity of opposite sign is drawn to the side nearest the inducing body, and that of like sign is repelled to the remote side, and these quantities are equal in amount.